JPS58171777A - Detection for address mark of magnetic disc device - Google Patents

Detection for address mark of magnetic disc device

Info

Publication number
JPS58171777A
JPS58171777A JP5301082A JP5301082A JPS58171777A JP S58171777 A JPS58171777 A JP S58171777A JP 5301082 A JP5301082 A JP 5301082A JP 5301082 A JP5301082 A JP 5301082A JP S58171777 A JPS58171777 A JP S58171777A
Authority
JP
Japan
Prior art keywords
index mark
address
decoder
address mark
mark detection
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP5301082A
Other languages
Japanese (ja)
Inventor
Yasumori Hibi
日比　康守
Yasuo Fujiwara
藤原　泰夫
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP5301082A priority Critical patent/JPS58171777A/en
Publication of JPS58171777A publication Critical patent/JPS58171777A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B27/00—Editing; Indexing; Addressing; Timing or synchronising; Monitoring; Measuring tape travel
    • G11B27/10—Indexing; Addressing; Timing or synchronising; Measuring tape travel
    • G11B27/102—Programmed access in sequence to addressed parts of tracks of operating record carriers
    • G11B27/105—Programmed access in sequence to addressed parts of tracks of operating record carriers of operating discs

Landscapes

  • Indexing, Searching, Synchronizing, And The Amount Of Synchronization Travel Of Record Carriers (AREA)

Abstract

PURPOSE:To read out an address mark of a record surely, by stopping the address mark detection in a certain section by an index mark. CONSTITUTION:A counter 1 is counted up by a byte clock (a) and is reset by an index mark detection signal (b). When the counter 1 counts the time from the read-out of the index mark to the time when a magnetic head reaches the last position of a data field D of a record R0, namely, the time when the magnetic head runs for a length l, the counter 1 transmits a signal to a decoder 2, and the decoder 2 transmits a pulse to an output C to reset a flip flop 3. Since the flip flop 3 is set by the index mark detection signal (b), the Q terminal falls by the index mark detection signal (b) and rises by the output C of the decoder 2.

Description

【発明の詳細な説明】 （１）発明の技術分野 本発明は磁気ディスク装置の可変長製磁気記帰方式１こ
より１鍮され媒体面欠陥処理方法を用いた配録情報より
アドレスＶ−り【検出する磁気ディスク装置のアドレス
マーク検出方式に関する。DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a variable-length magnetic recording method for a magnetic disk device, and a method for processing address V-reference from recorded information using a medium surface defect processing method. The present invention relates to an address mark detection method for a magnetic disk device.

（ｂ）　　従来技術と問題点 可変長型磁気配骨方式會用いて情報を１会する磁気ディ
スク装置−こは十位の磁気ディスク制御装置よりトラッ
ク−周のどの位置に磁気ヘッドがありてもアドレスマー
クの検出命令が発ゼられる。(b) Prior Art and Problems A magnetic disk device that collects information using a variable-length magnetic arrangement system - This is a magnetic disk control device of 10 positions, regardless of where the magnetic head is located on the track. An address mark detection command is issued.

可変＊Ｗ磁気配帰方式による磁気ディスク媒体上に形成
されるトラックの通常のフォーマット管第１ＷＪに示す
、Ｂはインデックスマークでトラック−周の基準点を示
す、ＨＡはホームアドレス、Ｃはカウントフィールド、
Ｄはデータフィールド、ＲＯ，Ｒ１はレコードである。Normal format of tracks formed on magnetic disk media by variable*W magnetic distribution method. Shown in tube No. 1 WJ, B is an index mark and indicates the reference point of the track circumference, HA is the home address, and C is the count field. ,
D is a data field, and RO and R1 are records.

ＡＭはアドレスマークである。第１図のトラックフォー
マットならばホームアドスＨＡ、　レコードＲＯのカウ
ントフィールドＣ１データフィールドＤと願に読出しア
ドレスマーク検出方式んでも、又読出し時間節減のため
ホームアドレスＨＡ、レコードＲＯ１−トｔ’？して直
接アドレス！−りＡＭ（−読出しても問題はないが、第
２図の如く磁気ディスク媒体上ｌこキズがあり媒体面欠
陥処理方法により該キズをスキップする処理管行なった
ＳＤが存在すると、前記の［１１アドレスマークＡＭｔ
読出す命令の場合キズの畏さによりアドレスマークＡＭ
と誤認される場合がありレコードＲ１を読出す筈の所ホ
ームアドレスＪＡｔ読出すこととなる欠点がある。AM is an address mark. In the track format shown in Fig. 1, the home address HA, record RO count field C1 data field D, and the read address mark detection method are used to save the read time. Then address directly! - There is no problem when reading AM (-), but if there is an SD that has some scratches on the magnetic disk medium as shown in Figure 2 and has been processed to skip the scratches using the media surface defect processing method, then the above-mentioned [ 11 address mark AMt
In the case of a read command, the address mark AM
There is a drawback that the home address JAt is read instead of the record R1.

（ｃ）　　発明の目的 本発明の目的は上記欠点１除くためインデックスマーク
より一定区間アドレスマーク検出を阻止すること−こよ
りレコードＲ１のアドレス！−り會ｉ実ｌこ読出す手段
を提供することにある。(c) Purpose of the Invention The purpose of the present invention is to prevent the detection of an address mark in a certain interval from the index mark in order to eliminate the above-mentioned drawback 1 - the address of record R1! - It is an object of the present invention to provide a means for reading out the actual results of a meeting.

（ｄ）　　発明の構成 本発明の構成はインデックスマークＢからレコードＲＯ
のデータフィールドＤの最後迄の距離即ち第２図のｔで
示す距離が一定であることに着目しインデックスマーク
會検出したら一定区間即ちｔの区間経過した後アドレス
マークの検出を開始する回路を設けたものである。(d) Structure of the Invention The structure of the present invention is from index mark B to record RO.
Focusing on the fact that the distance to the end of the data field D, that is, the distance indicated by t in FIG. It is something that

（ｅ）　　発明の実施例 ＩＦＩａ図は本発明の一実施例を示す回路図である。(e) Examples of the invention The IFIa diagram is a circuit diagram showing one embodiment of the present invention.

第４図は第３図の動作管説明するタイムチャートである
。第４図ａ　−ｆの記号は第３図の同紀号の位置のタイ
ミング【示す。FIG. 4 is a time chart illustrating the operating tube of FIG. 3. The symbols in FIG. 4 a to f indicate the timing of the position of the same period number in FIG. 3.

カウンタ（ＣＮＴ　）１はバイトクロック１により歩進
しインデックマーク検出信号すによりりセットされる。Counter (CNT) 1 is incremented by byte clock 1 and set by index mark detection signal.

カウンタ１は磁気ヘッドが、第２５！ｌＢで示すインデ
ックスｉ−り會読出してからレコードＲＯのデータフィ
ールドＤの最後の位置に達する時間即ちｔの距１Ｉｌｌ
ｉｔ−走行する時間計数するとデコーダ（ＤＥＣ）２に
信号を送出し、デコーダ２は出力Ｃζこパルス【送出し
フリップフロツプ（ＦＦ’　）３にリセットする。フリ
ップ７０ツブ３はインデックスｉ−り検出信号ｂＩこよ
りセットされるため、Ｑ端子は第４図ｅに示す如くイン
デックスマーク検出信号すで立下り、デコーダ２の出力
Ｃで立上る。アドレスマーク読出し命令ＡＭリサーチｄ
は立上ったま＼のためＡＮＤ回路４の出力はＡＭサーチ
で立上りフリップ７０ツグＱの立下りで立下り、すの再
度の立上〇で立上り出力に第４図ｆで示す如く了ドレス
マーク検出信号を送出する。Counter 1 has the magnetic head number 25! The index i denoted by lB - the time from reading to the last position of the data field D of the record RO, i.e. the distance t 1Ill
When it counts the running time, it sends a signal to the decoder (DEC) 2, and the decoder 2 resets the output Cζ to the output flip-flop (FF') 3. Since the flip 70 block 3 is set by the index i-reduction detection signal bI, the index mark detection signal at the Q terminal has already fallen and rises at the output C of the decoder 2, as shown in FIG. Address mark read command AM research d
remains rising, so the output of the AND circuit 4 rises in the AM search, and falls at the fall of flip 70, and when it rises again, it rises and a dress mark is placed on the output as shown in Figure 4 f. Sends a detection signal.

（ｆ）　　発明の詳細 な説明した如く本発明は磁気ディスク媒体面のキズによ
り誤ったデータを読出すミスを防止することが可能でそ
の効果は大なるものがある。(f) Detailed Description of the Invention As described above, the present invention is capable of preventing mistakes in reading incorrect data due to scratches on the surface of a magnetic disk medium, and has a great effect.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は通常のトラックフォーマット管説明する図、第
２図は媒体面欠陥処理方法音用いて処理されたトラック
フォーマットを説明する図、第３図は本発明の一実施例
を示す回路図、第４図は第３図の動作ｔｉｌｌ？明する
タイムチャートである。 】はカウンタ、２はデコーダ、３はフリップ７０ツグ、
４はＡＮＤ回路である。FIG. 1 is a diagram illustrating a normal track format tube, FIG. 2 is a diagram illustrating a track format processed using a medium surface defect processing method, and FIG. 3 is a circuit diagram showing an embodiment of the present invention. Figure 4 shows the operation of Figure 3 till? This is a time chart to explain the situation. ] is the counter, 2 is the decoder, 3 is the flip 70 tsug,
4 is an AND circuit.

Claims (1)

【特許請求の範囲】 磁気ディスク装置の可変長型磁気配録方式により配置さ
れたアドレス！−りｔ検出する方式に於て、インデック
スマークより一定区間経過した後アドレス！−りの検出
を行なう手段【設けた事を特命とする磁気ディスク装置
のアドレスマーク検出方式。[Claims] Addresses arranged by a variable length magnetic recording method of a magnetic disk device! - In the method of detecting the address after a certain period has elapsed from the index mark! - Means for detecting errors [Address mark detection method for magnetic disk drives that is specially designed to be provided.
JP5301082A 1982-03-31 1982-03-31 Detection for address mark of magnetic disc device Pending JPS58171777A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP5301082A JPS58171777A (en) 1982-03-31 1982-03-31 Detection for address mark of magnetic disc device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP5301082A JPS58171777A (en) 1982-03-31 1982-03-31 Detection for address mark of magnetic disc device

Publications (1)

Publication Number Publication Date
JPS58171777A true JPS58171777A (en) 1983-10-08

Family

ID=12930934

Family Applications (1)

Application Number Title Priority Date Filing Date
JP5301082A Pending JPS58171777A (en) 1982-03-31 1982-03-31 Detection for address mark of magnetic disc device

Country Status (1)

Country Link
JP (1) JPS58171777A (en)

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